It’s not clear what causes the thyroid disease but even though there’s no cure, the symptoms can be treated.

But for Rachel, it’s not just been a physical problem.

“When the disease flares up, it’s so hard to deal with that mentally, things can be very tough,” she says.

Rachel’s shown signs of anxiety since a young age but this developed into depression as the disease got more serious in her late teens.

“When it flares up, the best way I can describe it is like having really bad flu. You’re really achy and weak and your brain is in a huge fog – it’s hard to get the right words out or remember what you’re doing.”

Rachel says she’s got more accepting of her position over the last year or so – and is pleased Gigi Hadid is raising the disease’s profile.

“Whether it’s down to feeling physically feeling tired or weight gain and weight loss, we shouldn’t be judging people on how they look.

“There’s so much more in a person than their physical appearance.”

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